Westonci.ca is the premier destination for reliable answers to your questions, provided by a community of experts. Get immediate and reliable solutions to your questions from a community of experienced experts on our Q&A platform. Connect with a community of professionals ready to help you find accurate solutions to your questions quickly and efficiently.

\begin{tabular}{cccc}
Tahoe & 20 & 30 & 40 \\
Utah & 10 & 30 & 60 \\
Colorado & 10 & 40 & 50
\end{tabular}

a. [tex]$df=$[/tex] [tex]$\square$[/tex] 2

b. What is the [tex]$\chi^2$[/tex] test statistic? [tex]$\square$[/tex]

c. What is the [tex]$p$[/tex]-value? If your answer is less than .01, write 0. [tex]$\square$[/tex]

d. Do we reject the null hypothesis at [tex]$\alpha=.05$[/tex]?

[tex]$\rightarrow$[/tex] A. Yes

B. No


Sagot :

To solve this problem, let's go through it step-by-step using the information provided.

### Part a: Degrees of Freedom (df)

The degrees of freedom in a chi-square test for independence is calculated using the formula:
[tex]\[ \text{df} = (r - 1) \times (c - 1) \][/tex]
where [tex]\( r \)[/tex] is the number of rows and [tex]\( c \)[/tex] is the number of columns in the contingency table.

The provided table has 3 rows (Tahoe, Utah, Colorado) and 3 columns (not labeled but there are three data points in each row). So:
[tex]\[ \text{df} = (3 - 1) \times (3 - 1) = 2 \times 2 = 4 \][/tex]

So, the degrees of freedom is:
[tex]\[ \boxed{4} \][/tex]

### Part b: Chi-Square Test Statistic ([tex]\(\chi^2\)[/tex] statistic)

The chi-square test statistic provided is:
[tex]\[ \chi^2 \approx 10.5259 \][/tex]

So, the chi-square test statistic is:
[tex]\[ \boxed{10.5259} \][/tex]

### Part c: p-Value

The given p-value is:
[tex]\[ p \approx 0.0324 \][/tex]

As the p-value is greater than 0.01, we don't need to write 0.

So, the p-value is:
[tex]\[ \boxed{0.0324} \][/tex]

### Part d: Decision at [tex]\(\alpha = 0.05\)[/tex]

To decide whether to reject the null hypothesis, compare the p-value to the significance level ([tex]\(\alpha = 0.05\)[/tex]).

The rule is:
- If [tex]\( p < \alpha \)[/tex], reject the null hypothesis.
- If [tex]\( p \geq \alpha \)[/tex], do not reject the null hypothesis.

Given [tex]\( p \approx 0.0324 \)[/tex], which is less than [tex]\( 0.05 \)[/tex]:
[tex]\[ 0.0324 < 0.05 \][/tex]

Therefore, we reject the null hypothesis at [tex]\(\alpha = 0.05\)[/tex].

So, the answer is:
[tex]\[ \boxed{\rightarrow \odot \text{A. Yes}} \][/tex]

In summary:
- Degrees of freedom: [tex]\(\boxed{4}\)[/tex]
- Chi-square test statistic: [tex]\(\boxed{10.5259}\)[/tex]
- p-value: [tex]\(\boxed{0.0324}\)[/tex]
- Reject the null hypothesis at [tex]\(\alpha = 0.05\)[/tex]? [tex]\(\boxed{\rightarrow \odot \text{A. Yes}}\)[/tex]
Thanks for using our service. We're always here to provide accurate and up-to-date answers to all your queries. We hope this was helpful. Please come back whenever you need more information or answers to your queries. Thank you for choosing Westonci.ca as your information source. We look forward to your next visit.